Abstract: Mutated Lactobacillus brevis strain 269Y ?-glucuronidase enzymes with enhanced enzymatic activity at low pH (e.g., below pH 6.8), as well as enhanced thermostability as compared to wild type enzyme are provided. The enzymes of the invention advantageously allow for accurate analysis of bodily samples for the presence of drugs at low pH and in 30 minutes or less, as compared to the several hours needed using prior enzyme preparations. Methods of using the mutated enzymes for hydrolysis of glucuronide substrates, including opiates and benzodiazepines, are also provided.

Abstract: Mutated Staphylococcus sp. RLH1 ?-glucuronidase enzymes with enhanced enzymatic activity and thermostability as compared to wild type enzyme are provided. The enzymes of the invention advantageously allow for accurate analysis of bodily samples for the presence of drugs in 30 minutes or less, as compared to the several hours needed using prior enzyme preparations. Methods of using the mutated enzymes for hydrolysis of glucuronide substrates, including opiates and benzodiazepines, are also provided.